Keep your musician in tune with this cool tuner pedal. It has a colorful digital display and plugs into your power brick. The display is easy to read, which is important if you are playing in a dark bar. A 9 volt power supply is required, and not included. This is a common size, and not hard to find, if you don't already have one around. (We did.) The accuracy is unsurpassed by other tuner and it is so easy to use. Just plug it in and turn it on. #Mugig #rankboosterreview #sponsored